This invention relates to prosthodontic restorations, and, particularly, dental implants or prosthesis whereby a fixture, typically titanium, is surgically implanted in the edentulous area of the alveolar bone as a substitute for a missing natural tooth root.
Today, dental restorations are frequently coupled with titanium implants placed in a patient's bone structure underlying missing teeth for the purpose of replacing the lost teeth. Osseointegration, the bonding between the bone and implant, firmly anchors the implant fixture in place to provide a secure base for the prosthesis. In this regard, a titanium transmucosal abutment is connected to the implant fixture with a screw. The abutment thereby emerges from the patient's soft tissue or gum and provides the structure upon which to mount the restoration. A restoration, shaped like a tooth and having an internally mounted cylinder, is typically connected to the abutment by either cement or a screw.
The use of dental implants has become increasingly popular since their commercial introduction. Initial attention of implant restoration of the mouth was focused on the achievement of sound integration of the titanium fixtures to the surrounding bone. Success was determined by the degree of osseointegration. As the dental community relied more and more on this field of prosthodontics, a variety of implants and appliances became available. However, the concentration on providing biocompatible fixtures in the mouth, resulted in inadequate attention being paid to providing restorations that are esthetic and integrate fully and are more compatible to the patient's gums and gum line.
In natural teeth, the gingival contour interproximally (mesial and distal) is greater than the facial or lingual contour.
In conventional fixed prosthodontics, tooth preparation for full coverage, restorations follow the contour of the gingival margin. The tooth preparation interproximally is more coronal than the facial or lingual. The tooth preparation is scalloped to follow the gingival margin mesiodistally across the facial and lingual.
All implants abutments of dental prostheses available today are the same height coronally along the gingival margin for complete 360.degree.. The gingival portion of the conventional abutments do not follow the contour of the gingiva. Since the interproximal tissue is higher coronally, the papilla are unsupported by the abutment, and, consequently, they tend to collapse towards the abutment resulting in potential health problems, improper and undesirable gingiva contour and an esthetically unattractive gum line.